http://bugzilla.suse.com/show_bug.cgi?id=1168914 Bug ID: 1168914 Summary: RAID module uses metadata=1.0 and therefore can't use journal feature for RAID5 Classification: openSUSE Product: openSUSE Tumbleweed Version: Current Hardware: Other OS: Other Status: NEW Severity: Normal Priority: P5 - None Component: YaST2 Assignee: yast2-maintainers@suse.de Reporter: psikodad@gmx.de QA Contact: jsrain@suse.com Found By: --- Blocker: --- Summary: yast partitioner creates raid devices always with "metadata=1.0" and therefore it's not possible to add a journal to a RAID5 device. Workaround: Create the RAID5 manually, because then the default metadata version 1.2 is used, which supports journal. When I create a new RAID5 with YaST2 partitioner (storage-ng), then the raid version (metadata) is always 1.0. In fact it's hard coded in file libstorage-ng-master/storage/Devices/MdImpl.cc: string cmd_line = MDADM_BIN " --create " + quote(get_name()) + " --run --level=" + boost::to_lower_copy(toString(md_level), locale::classic()) + " --metadata=1.0" " --homehost=any"; A few years ago mdadm got a new feature to fight the "write hole" of RAID5: journaling. see https://www.kernel.org/doc/Documentation/md/raid5-cache.txt I would like the test it (--add-journal), but it's not working: # mdadm --detail /dev/md127 /dev/md127: Version : 1.0 Creation Time : Tue Apr 7 22:39:34 2020 Raid Level : raid5 Array Size : 16776960 (16.00 GiB 17.18 GB) Used Dev Size : 8388480 (8.00 GiB 8.59 GB) Raid Devices : 3 ... Number Major Minor RaidDevice State 0 8 16 0 active sync /dev/sdb 1 8 32 1 active sync /dev/sdc 3 8 48 2 active sync /dev/sdd # mdadm --manage /dev/md127 --readonly --add-journal /dev/sde mdadm: Failed to hot add /dev/sde as journal, please try restart /dev/md127. # mdadm --stop /dev/md127 mdadm: stopped /dev/md127 # mdadm --assemble /dev/md127 /dev/sd[bcd] mdadm: /dev/md127 has been started with 3 drives. # mdadm --manage /dev/md127 --readonly --add-journal /dev/sde mdadm: Failed to hot add /dev/sde as journal, please try restart /dev/md127. ------------ However, it works when metadata=1.2 (which is the default for mdadm) tw2019:/home/dom # mdadm --stop /dev/md127 mdadm: stopped /dev/md127 tw2019:/home/dom # mdadm --create /dev/md127 --level=5 --raid-devices=3 /dev/sd[bcd] mdadm: /dev/sdb appears to be part of a raid array: level=raid5 devices=3 ctime=Tue Apr 7 22:39:34 2020 mdadm: /dev/sdc appears to be part of a raid array: level=raid5 devices=3 ctime=Tue Apr 7 22:39:34 2020 mdadm: /dev/sdd appears to be part of a raid array: level=raid5 devices=3 ctime=Tue Apr 7 22:39:34 2020 Continue creating array? y mdadm: Defaulting to version 1.2 metadata mdadm: array /dev/md127 started. # mdadm --detail /dev/md127 /dev/md127: Version : 1.2 Creation Time : Tue Apr 7 22:47:35 2020 Raid Level : raid5 Array Size : 16758784 (15.98 GiB 17.16 GB) Used Dev Size : 8379392 (7.99 GiB 8.58 GB) Raid Devices : 3 ... Number Major Minor RaidDevice State 0 8 16 0 active sync /dev/sdb 1 8 32 1 active sync /dev/sdc 3 8 48 2 active sync /dev/sdd # mdadm --manage /dev/md127 --readonly --add-journal /dev/sde mdadm: Journal added successfully, making /dev/md127 read-write mdadm: added /dev/sde # mdadm --detail /dev/md127 /dev/md127: Version : 1.2 Creation Time : Tue Apr 7 22:47:35 2020 Raid Level : raid5 Array Size : 16758784 (15.98 GiB 17.16 GB) Used Dev Size : 8379392 (7.99 GiB 8.58 GB) Raid Devices : 3 Total Devices : 4 Persistence : Superblock is persistent Update Time : Tue Apr 7 22:48:48 2020 State : clean Active Devices : 3 Working Devices : 4 Failed Devices : 0 Spare Devices : 0 Layout : left-symmetric Chunk Size : 512K Consistency Policy : journal Name : tw2019:127 (local to host tw2019) UUID : 5dec6792:8109c604:970842a7:44f0d9e8 Events : 19 Number Major Minor RaidDevice State 0 8 16 0 active sync /dev/sdb 1 8 32 1 active sync /dev/sdc 3 8 48 2 active sync /dev/sdd 4 8 64 - journal /dev/sde => Use the default metadata (1.2) for new RAID devices. For RAID1 there could be some reasons to stick with version 1.0. See also : yast-storage-ng-master/src/lib/y2storage/boot_requirements_strategies/uefi.rb # EFI in RAID can work, but it is not much reliable. # See bsc#1081578#c9, FATE#322485, FATE#314829 # - RAID metadata must be somewhere where it will not interfere with UEFI reading # the disk. libstorage-ng currently uses "mdadm --metadata=1.0" which is OK # - The partition boot flag must be on # - The partition RAID flag must be on (but setting it resets the boot flag) -- You are receiving this mail because: You are on the CC list for the bug.